Download or read book A SEARCH FOR TIME DEPENDENT B0 S ANTI B0 S OSCILLATIONS USING EXCLUSIVELY RECONSTRUCTED D S MESONS written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A search for B[sub s][sup 0]-[bar B][sub s][sup 0] oscillations is performed using a sample of 400,000 hadronic Z[sup 0] decays collected by the SLD experiment. The B[sub s][sup 0] candidates are reconstructed in the B[sub s][sup 0][yields] D[sub s][sup -] X channel with D[sub s][sup -][yields][phi][pi][sup -], K*[sup 0] K[sup -]. The B[sub s][sup 0] production flavor is determined using the large forward-backward asymmetry of polarized Z[sup 0][yields] b[bar b] decays and charge information in the hemisphere opposite that of the B[sub s][sup 0] candidate. The decay flavor is tagged by the charge of the D[sub s][sup[+-]]. From a sample of 361 candidates with an average B[sub s][sup 0] purity of 40%, we exclude the following values of the oscillation frequency:[Delta]m[sub s]
Download or read book A Search for Time Dependent B sub S sup 0 bar B sub S sup 0 Oscillations Using Exclusively Reconstructed D sub S sup AT SLD written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors set a preliminary 95% C.L. exclusion on the oscillation frequency of B[sub s][sup 0] -[bar B][sub s][sup 0] mixing using a sample of 400,000 hadronic Z[sup 0] decays collected by the SLD experiment at the SLC during the 1996-98 run. In this analysis, B[sub s][sup 0] mesons are partially reconstructed by combining a fully reconstructed D[sub s] with other B[sub s][sup 0] decay products. The D[sub s] decays are reconstructed via the[phi][pi] and K*K channels. The b-hadron flavor at production is determined by exploiting the large forward-backward asymmetry of polarized Z[sup 0][yields] b[bar b] decays as well as information from the hemisphere opposite to the reconstructed B decay. The flavor of the B[sub s][sup 0] at the decay vertex is determined by the charge of the D[sub s]. A total of 361 candidates passed the final event selection cuts. This analysis excludes the following values of the B[sub s][sup 0]-[bar B][sub s][sup 0] mixing oscillation frequency:[Delta]m[sub s]
Download or read book A Search for Time Dependent B sub S bar B sub S Oscillations Using Exclusively Reconstructed D sub S AT SLD written by and published by . This book was released on 2002 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors set a preliminary 95% C.L. exclusion on the oscillation frequency of B{sub s}° - {bar B}{sub s}° mixing using a sample of 400,000 hadronic Z° decays collected by the SLD experiment at the SLC during the 1996-98 run. In this analysis, B{sub s}° mesons are partially reconstructed by combining a fully reconstructed D{sub s} with other B{sub s}° decay products. The D{sub s} decays are reconstructed via the [phi][pi] and K*K channels. The b-hadron flavor at production is determined by exploiting the large forward-backward asymmetry of polarized Z° 2!b{bar b} decays as well as information from the hemisphere opposite to the reconstructed B decay. The flavor of the B{sub s}° at the decay vertex is determined by the charge of the D{sub s}. A total of 361 candidates passed the final event selection cuts. This analysis excludes the following values of the B{sub s}°-{bar B}{sub s}° mixing oscillation frequency: [Delta]m{sub s}
Download or read book Time Dependent B sub S bar B sub S Oscillations Using Exclusively Reconstructed D sub S Decays at SLD written by and published by . This book was released on 2000 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: We set a preliminary 95% C.L. exclusion on the oscillation frequency of B{sub s}° - {bar B}{sub s}° mixing using a sample of 400,000 hadronic Z° decays collected by the SLD experiment at the SLC during the 1996-98 run. In this analysis, B{sub s}° mesons are partially reconstructed by combining a fully reconstructed D{sub s} with other B{sub s}° decay tracks. The D{sub s} decays are reconstructed via the [phi][pi] and K*K channels. The b-hadron flavor at production is determined by exploiting the large forward-backward asymmetry of polarized Z° 2!b{bar b} decays as well as information from the hemisphere opposite to the reconstructed B decay. The flavor of the B{sub s}° at the decay vertex is determined by the charge of the D{sub s}. A total of 361 candidates passed the final event selection cuts. This analysis excludes the following values of the B{sub s}°-{bar B}{sub s}° mixing oscillation frequency: [Delta]m{sub s}
Download or read book Time Dependent B sub S sup 0 bar B sub S sup 0 Oscillations Using Exclusively Reconstructed D sub S sup Decays at SLD written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We set a preliminary 95% C.L. exclusion on the oscillation frequency of B[sub s][sup 0] -[bar B][sub s][sup 0] mixing using a sample of 400,000 hadronic Z[sup 0] decays collected by the SLD experiment at the SLC during the 1996-98 run. In this analysis, B[sub s][sup 0] mesons are partially reconstructed by combining a fully reconstructed D[sub s] with other B[sub s][sup 0] decay tracks. The D[sub s] decays are reconstructed via the[phi][pi] and K*K channels. The b-hadron flavor at production is determined by exploiting the large forward-backward asymmetry of polarized Z[sup 0][yields] b[bar b] decays as well as information from the hemisphere opposite to the reconstructed B decay. The flavor of the B[sub s][sup 0] at the decay vertex is determined by the charge of the D[sub s]. A total of 361 candidates passed the final event selection cuts. This analysis excludes the following values of the B[sub s][sup 0]-[bar B][sub s][sup 0] mixing oscillation frequency:[Delta]m[sub s]
Download or read book Search for Time Dependent B0s B0s bar Oscillations Using a Vertex Charge Dipole Technique written by and published by . This book was released on 2002 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: We report a search for B{sub s}° - {bar B}{sub s}° oscillations using a sample of 400,000 hadronic Z° decays collected by the SLD experiment. The analysis takes advantage of the electron beam polarization as well as information from the hemisphere opposite that of the reconstructed B decay to tag the B production flavor. The excellent resolution provided by the pixel CCD vertex detector is exploited to cleanly reconstruct both B and cascade D decay vertices, and tag the B decay flavor from the charge difference between them. We exclude the following values of the B{sub s}° - {bar B}{sub s}° oscillation frequency: [Delta]m{sub s}
Download or read book Time Dependent B sub S bar B sub S Mixing Using Inclusive and Semileptonic B sup S Decays at SLD written by and published by . This book was released on 1998 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors set a preliminary 95% C.L. exclusion on the oscillation frequency of B{sub s}°-{anti B}{sub s}° mixing using a sample of 250,000 hadronic Z° decays collected by the SLD experiment at the SLC between January 1996 and March 1998. The analyses determine the b-hadron flavor at production by exploiting the large forward-backward asymmetry of polarized Z° 2!b{anti b} decays as well as information from the hemisphere opposite that of the reconstructed B decay. In one analysis, B decay vertices are reconstructed inclusively with a topological technique, and separation between B{sub s}° and {anti B}{sub s}° decays exploits the B{sub s}° 2!D{sub s}− cascade charge structure. The other analysis selects semileptonic decays reconstructed by intersecting a lepton with he trajectory of a topologically reconstructed D meson. The two analyses are combined to exclude the following values of the B{sub s}°-{anti B}{sub s}° mixing oscillation frequency: [Delta]m{sub s}
Download or read book Time Dependent B sub S bar B sub S Mixing Using Inclusive and Semileptonic B Decays at SLD written by and published by . This book was released on 1999 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt: We set a preliminary 95% C.L. exclusion on the oscillation frequency of B{sub s}°-{bar B}{sub s}° mixing using a sample of 350,000 hadronic Z° decays collected by the SLD experiment at the SLC during the 1997-98 run. The analyses determine the b-hadron flavor at production by exploiting the large forward-backward asymmetry of polarized Z° 2!b{bar b} decays as well as information from the hemisphere opposite that of the reconstructed B decay. In one analysis, B decay vertices are reconstructed inclusively with a new topological technique, and separation between B{sub s}° and {bar B}{sub s}° decays exploits the B{sub s}° 2!D{sub s}− cascade charge structure. In the other analysis, semileptonic decays are selected and the B decay point is reconstructed by intersecting a lepton track with the trajectory of a topologically reconstructed D meson. The two analyses are combined with a third analysis described elsewhere to exclude the following values of the B{sub s}°-{bar B}{sub s}° mixing oscillation frequency: [Delta]m{sub s}
Download or read book A Study of Neutral B Meson Time Evolution Using Exclusively Reconstructed Semileptonic Decays written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Standard Model of particle physics describes the fundamental building blocks of the Universe and their basic interactions. The model naturally describes the time evolution of the basic particles, of which lifetime and mixing are two examples. The neutral B meson, consisting of a bottom quark and an oppositely charged down quark, enjoys a lifetime of about 1.5 ps and the special property of mixing with its antiparticle partner, the [bar B][sup 0]. That is, due to second order weak interactions, the B[sup 0] meson can change into a [bar B][sup 0] meson and back again as it evolves through time. The details of this behavior offer an opportunity to closely examine the Standard Model. In this dissertation, I report on a measurement of the lifetime and mixing frequency of the neutral B meson. Using the semileptonic decay channel B[sup 0] [yields] D*[sup -][ell][sup +][bar [nu]][sub [ell]], we select more than 68,000 signal and background candidates from about 23 million B[bar B] pairs collected in 1999-2000 with the BABAR detector located at the Stanford Linear Accelerator Center. The other B in the event is reconstructed inclusively. By constructing a master probability density function that describes the distribution of decay time differences in the sample, we use a maximum likelihood technique to simultaneously extract the B[sup 0] lifetime and mixing parameters with precision comparable to the year 2000 world average. The results are [tau][sub B[sup 0]] = (1.523[sub -0.023][sup +0.024] [+-] 0.022) ps and [Delta]m[sub d] = (0.492 [+-] 0.018 [+-] 0.013) ps[sup -1]. The statistical correlation coefficient between [tau][sub B[sup 0]] and [Delta]m[sub d] is -0.22. I describe in detail several cutting-edge strategies this analysis uses to study these phenomena, laying important groundwork for the future. I also discuss several extensions of this work to include possible measurements of higher order parameters such as [Delta][Lambda][sub d].
Download or read book Observation of B0 s Anti B0 s Oscillations written by and published by . This book was released on 2006 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors report the observation of B{sub s}°-{bar B}{sub s}° oscillations from a time-dependent measurement of the B{sub s}°-{bar B}{sub s}° oscillation frequency [Delta]m{sub s}. Using a data sample of 1 fb−1 of p{bar p} collisions at √s = 1.96 TeV collected with the CDF II detector at the Fermilab Tevatron, they find signals of 5600 fully reconstructed hadronic B{sub s} decays, 3100 partially reconstructed hadronic B{sub s} decays, and 61,500 partially reconstructed semileptonic B{sub s} decays. They measure the probability as a function of proper decay time that the B{sub s} decays with the same, or opposite, flavor as the flavor at production, and they find a signal for B{sub s}°-{bar B}{sub s}° oscillations. The probability that random fluctuations could produce a comparable signal is 8 x 10−8, which exceeds 5[sigma] significance. They measure [Delta]m{sub s} = 17.77 ± 0.10(stat) ± 0.07(syst) ps−1 and extract.
Download or read book A Study of Neutral B Meson Time Evolution Using Exclusively Reconstructed Semileptonic Decays written by T. Meyer and published by . This book was released on 2003 with total page 361 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Standard Model of particle physics describes the fundamental building blocks of the Universe and their basic interactions. The model naturally describes the time evolution of the basic particles, of which lifetime and mixing are two examples. The neutral B meson, consisting of a bottom quark and an oppositely charged down quark, enjoys a lifetime of about 1.5 ps and the special property of mixing with its antiparticle partner, the {bar B}{sup 0}. That is, due to second order weak interactions, the B{sup 0} meson can change into a {bar B}{sup 0} meson and back again as it evolves through time. The details of this behavior offer an opportunity to closely examine the Standard Model. In this dissertation, I report on a measurement of the lifetime and mixing frequency of the neutral B meson. Using the semileptonic decay channel B{sup 0} {yields} D*{sup -}{ell}{sup +}{bar {nu}}{sub {ell}}, we select more than 68,000 signal and background candidates from about 23 million B{bar B} pairs collected in 1999-2000 with the BABAR detector located at the Stanford Linear Accelerator Center. The other B in the event is reconstructed inclusively. By constructing a master probability density function that describes the distribution of decay time differences in the sample, we use a maximum likelihood technique to simultaneously extract the B{sup 0} lifetime and mixing parameters with precision comparable to the year 2000 world average. The results are {tau}{sub B{sup 0}} = (1.523{sub -0.023}{sup +0.024} {+-} 0.022) ps and {Delta}m{sub d} = (0.492 {+-} 0.018 {+-} 0.013) ps{sup -1}. The statistical correlation coefficient between {tau}{sub B{sup 0}} and {Delta}m{sub d} is -0.22. I describe in detail several cutting-edge strategies this analysis uses to study these phenomena, laying important groundwork for the future. I also discuss several extensions of this work to include possible measurements of higher order parameters such as {Delta}{Lambda}{sub d}.
Download or read book Measurement of the Time Dependence of B0 B0 bar Oscillations Using Inclusive Dilepton Events written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A preliminary study of time dependence of B[sup 0][bar B][sup 0] oscillations using dilepton events is presented. The flavor of the B meson is determined by the charge sign of the lepton. To separate signal leptons from cascade and fake leptons we have used a method which combines several discriminating variables in a neural network. The time evolution of the oscillations is studied by reconstructing the time difference between the decays of the B mesons produced by the[Upsilon](4S) decay. With an integrated luminosity of 7.7 fb[sup -1] collected on resonance by BABAR at the PEP-II asymmetric B Factory, we measure the difference in mass of the neutral B eigenstates, [Delta]m[sub B[sup 0]], to be (0.507[+-] 0.015[+-] 0.022) x 10[sup 12][Dirac-h] s[sup -1].
Download or read book Simultaneous Measurement of the B0 Meson Lifetime and Mixing Frequency with B0 D 1 Nu Decays written by and published by . This book was released on 2002 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: We measure the B° lifetime [tau]{sub b°} and the B°-{bar B}° oscillation frequency [Delta]m{sub d} with a sample of approximately 14,000 exclusively reconstructed B{sup 0} 2!D*− l [nu]{sub {ell}} signal events, selected from 23 million B{bar B} pairs recorded at the [Upsilon](4S) resonance with the BABAR detector at the Stanford Linear Accelerator Center. The decay position of the other B is determined with the remaining tracks in the event, and its b-quark flavor at the time of decay is determined with a tagging algorithm that exploits the correlation between the flavor of the b-quark and the charges of its decay products. The lifetime and oscillation frequency are measured simultaneously with an unbinned maximum-likelihood ([Delta]t) that uses, for each event, the measured difference in decay times of the two B mesons ([Delta]t), the calculated uncertainty on [Delta]t, the signal and background probabilities, and b-quark tagging information for the other B. The results are [tau]{sub B{sup 0}} = (1.523{sub -0.023}{sup +0.024} ± 0.022) ps and [Delta]m{sub d} = (0.492 ± 0.018 ± 0.013) ps−1.
Download or read book Search for B0 S Anti B0 S Oscillations at SLD written by and published by . This book was released on 2003 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present preliminary results on the time dependence of B{sub s}° - {bar B}{sub s}° and B{sub d}° - {bar B}{sub d}° mixing using a sample of 400,000 hadronic Z° decays collected by the SLD experiment at the SLC. The analyses take advantage of the excellent decay length resolution of the CCD vertex detector. The B or {bar B} production flavor is determined by exploiting the large forward-backward asymmetry of polarized Z° → b{bar b} decays. This flavor tag is enhanced by incorporating additional information from the hemisphere opposite that of the reconstructed B decay. The B{sub d}° - {bar B}{sub d}° mixing analysis uses the charge of high momentum kaons to identify the B or {bar B} decay flavor. The result is [Delta]m{sub d} = 0.503 ± 0.028(stat) ± 0.020(syst) ps−1. The results of three separate B{sub s}° - {bar B}{sub s}° mixing analyses are presented. These analyses determine the B decay flavor using the lepton charge in B semileptonic decays, the charge of fully reconstructed D{sub s} decays, and the charge difference between topologically reconstructed B and D decays. The three analyses are combined to set a lower limit on the B{sub s}° - {bar B}{sub s}° oscillation frequency of 12.0 ps−1 at 95% CL.
Download or read book A Study of B sup 0 bar B sup 0 Oscillations with Fully Reconstructed B Mesons with the BaBar Detector written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Time-dependent B[sup 0][bar B][sup 0] flavor oscillations are studied in e[sup+]e[sup -] annihilation data collected with the BABAR detector at center-of-mass energies near the[Upsilon](4S) resonance. We report a preliminary result for the time-dependent B[sup 0][bar B][sup 0] oscillation frequency, [Delta]m[sub d]= 0.512[+-] 0.017[+-] 0.022[Dirac-h] ps[sup -1].
Download or read book A Study of Neutral B Meson Time Evolution Using Exclusively Reconstructed Semieptonic Decays written by Timothy Issac Meyer and published by . This book was released on 2002 with total page 339 pages. Available in PDF, EPUB and Kindle. Book excerpt:
